1. Field of the Invention
This invention relates in general to motor vehicle electrical circuits, and in particular to a lane changing signaling device.
2. Description of the Prior Art
Conventional motor vehicles have signal lights for indicating when turning. The system includes lights on the front and rear which are connected through a mechanical lever switch to a flasher unit that provides interrupted or pulsating power. The mechanical lever is mounted to the steering column next to the steering wheel. When depressed in one direction, contacts are made to connect the flasher with the signal lights on one side of the vehicle. Pulling upward on the lever toward the other direction causes the other signal lights to flash. A mechanism within the lever switch will retain the connection until the turn is completed, at which time the lever automatically returns to its neutral position.
While this is satisfactory for making 90 degree turns, the system has deficiencies in regard to using it to indicate changing lanes. When changing lanes, normally the turn is not sharp enough to cause the mechanism, in the lever switch to automatically return when the lane change is completed. To avoid inadvertently leaving the lever on, one must engage the lever only slightly to a point short of its locked position. Still, it is very common to see motorists driving with a signal light erroneously flashing. Also, even if this does not accidentally occur, passing a car requires up to four movements of one's hand from the wheel to the lever. This is particularly a nuisance for persons that do a considerable amount of freeway driving, such as truck drivers.
U.S. Pat. No. 3,594,724, George A. Evers, issued July 20, 1971, shows a lane changing signal device that incorporates buttons on the steering wheel in conjunction with the conventional mechanical lever. The buttons provide a flashing signal when depressed. This allows one to change lanes without removing one's hands from the steering wheel. Also, it reduces the chances for inadvertently leaving the turn signal lever on.
U.S. Pat. No. 3,576,530, William R. Buechler et al., also shows a dual system. In both patents, it appears that both the lever and the push buttons could simultaneously operate. This might provide erroneous flashing on both sides of the vehicle, or no flashing at all. Both occurrences could lead to a dangerous situation. Also, both patents require the installation of slip rings to interconnect the button switches with the turn signal lights.